1. Field of the Invention
The present invention relates to a storage operation management system, and more particularly to an operation management technology of a storage area network (SAN) that decides an object range of a volume that is assumed to be an allocation candidate and a candidate volume based on policy information input regarding storage volume allocation from a user.
2. Description of the Prior Art
With the spread of an electronic business transaction and an increase in the utilization of multimedia data, the quantity of data an enterprise handles is increasing suddenly. As a result of this, an SAN technology that can handle a large amount of data effectively is spreading.
The flexibility of a business information system has increased by the installation of the SAN, but the configuration of storage equipment becomes complicated and the setting of the equipment a system administrator performs is also complicated. Further, because centralized control of storage has been enabled, not only the quantity of data handled by one system administrator increases but also an operating system (OS) of a business server and a type of a business application are increasing. Further, because the amount of data is inclined to increase day by day, the enhancement of the storage equipment and the allocation work of storage to the business server is being performed frequently.
In order to simplify a storage operation business in this manner, an operation technology that collects various types of condition elements and rules as policies, and names and defines the policy, then automatically decides a volume to be allocated by an operation based on the policies is becoming commonly accepted.
There are the following methods for specifying a volume selection policy that decides an object of storage allocation in the prior technology.
The first method explicitly specifies retrieval conditions of a volume that is assumed to be an allocation candidate as the policies. Classification of storage equipment that is assumed to be a candidate by a type name and specification such as types (RAID1 and RAID5) of RAID (Redundant Arrays of Inexpensive Disks) and drive configurations (3D+1P (one parity disk to three data disks)) are defined based on the policies.
The second method performs relative specification such as “High”, “Mid”, and “Low” respectively from the standpoint of performance and reliability or specification without levels as well as at three levels instead of specific specification as a type name, a RAID type, and a drive configuration of storage equipment. Even in a case like this, however, which of items is applicable to each of “High”, “Mid”, and “Low” inside an operation management system if they are expressed in the storage equipment type name, RAID type, and drive configuration? In most cases, they are associated statically.
Regarding this kind of the technology, a method for setting a logical area in a disk unit by preparing a table in which policies were registered, referring to this table when the logical area is set in the disk unit, and converting the table to performance and reliability information based on the policies is disclosed in Japanese Unexamined Patent Application Publication No. Hei 14 (2002)-222601, for example.
In the aforementioned methods, in the former method. It is difficult to realize the optimum volume allocation unless a user himself or herself is familiar with characteristics of storage according to the volume specifications. Further, in the latter method, because the distribution every user's storage specifications varies by a change in equipment configuration that arises from the expansion of storage equipment, the volume classified into “High” at a point of time will also be classified into “Mid” some time. Accordingly, the necessity of reviewing an association inside the operation management system occurs and the work that decides how the association should be reviewed is complicated and becomes a workload of the user. Further, even in either case, when the volume is allocated, there is a problem that the user must consider a difference in requirement characteristics every business application.